On Fri, Aug 30, 2013 at 04:10:42PM +0200, Toralf Förster wrote: > On 08/29/2013 03:30 PM, J. Bruce Fields wrote: > > On Thu, Aug 29, 2013 at 11:57:45AM +0200, richard -rw- weinberger wrote: > >> On Wed, Aug 28, 2013 at 7:21 PM, Toralf Förster <toralf.foerster@xxxxxx> wrote: > >>> On 08/27/2013 08:06 PM, J. Bruce Fields wrote: > >>>> On Tue, Aug 13, 2013 at 05:53:14PM -0400, bfields wrote: > >>>>> On Mon, Aug 12, 2013 at 04:36:40PM +0200, Jan Kara wrote: > >>>>>> On Sun 11-08-13 11:48:49, Toralf Förster wrote: > >>>>>>> so that the server either crashes (if it is a user mode linux image) or at least its reboot functionality got broken > >>>>>>> - if the NFS server is hammered with scary NFS calls using a fuzzy tool running at a remote NFS client under a non-privileged user id. > >>>>>>> > >>>>>>> It can re reproduced, if > >>>>>>> - the NFS share is an EXT3 or EXT4 directory > >>>>>>> - and it is created at file located at tempfs and mounted via loop device > >>>>>>> - and the NFS server is forced to umount the NFS share > >>>>>>> - and the server forced to restart the NSF service afterwards > >>>>>>> - and trinity is used > >>>>>>> > >>>>>>> I could find a scenario for an automated bisect. 2 times it brought this commit > >>>>>>> commit 68a3396178e6688ad7367202cdf0af8ed03c8727 > >>>>>>> Author: J. Bruce Fields <bfields@xxxxxxxxxx> > >>>>>>> Date: Thu Mar 21 11:21:50 2013 -0400 > >>>>>>> > >>>>>>> nfsd4: shut down more of delegation earlier > >>>>> > >>>>> Thanks for the report. I think I see the problem--after this commit > >>>>> nfs4_set_delegation() failures result in nfs4_put_delegation being > >>>>> called, but nfs4_put_delegation doesn't free the nfs4_file that has > >>>>> already been set by alloc_init_deleg(). > >>>>> > >>>>> Let me think about how to fix that.... > >>>> > >>>> Sorry for the slow response--can you check whether this fixes the > >>>> problem? > >>>> > >>> Yes. > >>> > >>> With the attached patch the problem can't be reproduced any longer with > >>> the prepared test case and current git kernels. > >> > >> BTW: Is nobody else fuzz testing NFS? > > > > I don't know. Toralf's reports are the only ones I recall off the top > > of my head, but I may have forgotten others. > > > > well, 7255e71 and 3c50ba8 I'd say. I don't know any 3c50ba8. 0c7c3e67 "nfsd4: don't close read-write opens too soon" and 64a817cf "nfsd4: reject "negative" acl lengths" are two other serious bugs found by your testing. I don't recall fuzz testing results from anyone else, but as I say I may have forgotten. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
